OpenStack for Architects - Second Edition

Writing the tests first

The second most important practice that we will pull from the software development world is that of test-driven development. We write the test that demonstrates the functionality we're implementing first and then work on the deployment until the test passes. Once the feature has been implemented, the test then becomes part of the routine monitoring system for the platform.

In our experience, if the tests aren't written before the code, they are frequently not written. Every project runs out of time at some point, and if the tests are the last thing on the list, they tend to get cut.